Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide the bench test device for simulating the plateau braking of the automobile, which can simulate the vacuum system test under different altitudes, so that the plateau test of a new automobile model is not limited by regions any more, and the development period and the cost of the automobile model are reduced; the invention also provides a use method of the test device for simulating the plateau braking bench of the automobile.
In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides a bench testing arrangement of simulation car plateau braking, includes simulation air chamber, vacuum pump I, vacuum pump II and is used for providing the car vacuum system of helping hand for car braking system, vacuum pump I passes through vacuum pipeline I and simulation air chamber intercommunication, and car vacuum system places in the simulation air chamber, and vacuum pump II passes through vacuum pipeline II and is connected with car vacuum system.
Further, the rack testing device further comprises a display screen and a control module, the display screen is connected with the control module, an air pressure sensor II used for detecting the pressure intensity in the simulation air chamber is arranged in the simulation air chamber, and the air pressure sensor II is connected with the control module.
Further, car vacuum system includes vacuum tank, booster and baroceptor I, and vacuum pump II communicates with vacuum tank through vacuum pipeline II, and vacuum tank passes through vacuum pipeline III and booster intercommunication, and baroceptor I passes through the pipeline and communicates with vacuum tank and detects car vacuum system's pressure.
Further, rack testing arrangement still includes brake pedal and stopper, is equipped with brake master cylinder and booster push rod on the booster, and brake pedal passes through the booster push rod to be connected with the booster, and the stopper passes through hydraulic pressure pipeline and is connected with the master cylinder on the booster.
Further, a controller is arranged between the vacuum tank and the booster, the controller is communicated with the vacuum pipeline III through a pipeline, and the controller is electrically connected with the control module.
Furthermore, the control module is internally provided with editable input and output software, a vacuum degree control strategy of the automobile vacuum system is input into the control module, a control signal for starting and stopping the vacuum pump II is from the equipment control module, and the starting and stopping frequency and the working time record are stored in the control module and displayed on a display screen.
Furthermore, a force sensor is arranged on the force application surface of the brake pedal, a stroke sensor is arranged on the push rod of the booster, a hydraulic pressure sensor is arranged on a hydraulic pipeline connected with the brake, and the force sensor, the stroke sensor and the hydraulic pressure sensor are all connected with the control module.
Furthermore, a one-way valve I is arranged on a vacuum pipeline I of the vacuum pump I and the simulation air chamber, and a one-way valve II is arranged on a vacuum pipeline II of the vacuum pump II and the vacuum tank.
The invention also relates to a use method of the test device for simulating the plateau braking bench of the automobile, which comprises the following steps:
step 1, inputting a vacuum degree control strategy of an automobile vacuum system into a control module;
step 2, when a plateau environment is simulated, the altitude and the atmospheric pressure of the plateau environment to be simulated are input into the control module, the vacuum pump I works to vacuumize the detection simulation air chamber to reach the air pressure value corresponding to the required plateau environment, and the vacuum pump II works to vacuumize the automobile vacuum system;
step 3, the control module controls the starting and stopping of the vacuum pump II according to the relation between the air pressure in the simulation air chamber and the air pressure of the vacuum system, and the starting and stopping frequency and working time records of the vacuum pump II are stored in the control module and displayed on the display screen;
and step 4, stepping on the brake pedal, testing and recording the test values of the vacuum degree of the automobile vacuum system, the starting and stopping threshold value of the vacuum pump II, the working time of the vacuum pump II, the force of the brake pedal, the stroke of the brake pedal, the hydraulic pressure and the like in the process according to different force and frequency applied to the brake pedal, and then comparing the test values with theoretical values to further optimize the design of each part of the automobile brake system.
The technical scheme adopted by the invention has the advantages that:
1. the bench test device for simulating the plateau braking of the automobile can edit and input the vacuum degree control strategy into the control module, set the altitude and the atmospheric pressure of the simulation air chamber after the control strategy is input, step on the brake pedal, according to different force, frequency and the like applied to the brake pedal, testing and recording the testing values of the vacuum degree of the automobile vacuum system, the starting and stopping threshold values of the vacuum pump II, the working time of the vacuum pump II, the brake pedal force, the brake pedal stroke, the hydraulic pressure and the like in the process, then comparing the test value with the theoretical value to optimize the design of each part of the automobile brake system, finally installing the optimized parts on the whole automobile, sending the whole automobile to a plateau area for testing, therefore, the automobile parts are designed optimally before the automobile parts are tested on the plateau, and the development cycle of new automobile models can be shortened to a certain extent.
2. The bench test device for simulating plateau braking of the automobile is not limited by regions, can test and test the automobile vacuum system and the relation among the brake pedal travel, the brake pedal force, the hydraulic pressure and the vacuum degree of the brake pedal at different altitudes in the same place, realizes quick, simple and effective verification, reduces the development period and the cost of the automobile type, and creates value for enterprises.
Detailed Description
In the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "planar direction", "circumferential", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
As shown in figure 1, a bench test device for simulating plateau braking of an automobile comprises a simulation air chamber 3, a vacuum pump I1, a vacuum pump II 2 and an automobile vacuum system for providing assistance for an automobile braking system, wherein the vacuum pump I1 is communicated with the simulation air chamber 3 through a vacuum pipeline I31, the automobile vacuum system is placed in the simulation air chamber 3, and the vacuum pump II 2 is connected with the automobile vacuum system through a vacuum pipeline II 32. The automobile vacuum system comprises a vacuum tank 41 (the volume of the vacuum tank is adjustable), a booster 42 and a pressure sensor I43, the vacuum pump II 2 is communicated with the vacuum tank 41 through a vacuum pipeline II 32, the vacuum tank 41 is communicated with the booster 42 through a vacuum pipeline III 44, and the pressure sensor I43 is communicated with the vacuum tank 41 through a pipeline to detect the pressure of the automobile vacuum system. In order to observe the internal condition of the simulation air chamber 3 conveniently, the simulation air chamber 3 is made of transparent materials such as acrylic materials. Vacuum pump I1 is according to actual different height above sea level atmospheric pressure evacuation for simulation air chamber 3 is close actual height above sea level atmospheric pressure.
In order to avoid gas backflow, a one-way valve I311 is arranged on a vacuum pipeline I31 through which the vacuum pump I1 is communicated with the simulation air chamber 3, and a one-way valve II 321 is arranged on a vacuum pipeline II 32 through which the vacuum pump II 2 is communicated with the vacuum tank 41.
Above-mentioned rack testing arrangement still includes display screen 5 and control module 6, and display screen 5 is connected with control module 6, is equipped with in the simulation air chamber 3 to be used for detecting the baroceptor II 33 of pressure in the simulation air chamber 3, and baroceptor I43 and baroceptor II 33 all are connected with control module 6. The control module 6 is internally provided with editable input and output software, a vacuum degree control strategy of the automobile vacuum system is input into the control module, a control signal for starting and stopping the vacuum pump II 2 is from the equipment control module, and the starting and stopping frequency and the working time record are stored in the control module 6 and displayed on the display screen 5. The control module corresponds to a VCU on the vehicle. The specific logic of the vacuum degree control strategy is as follows: different altitudes correspond to different atmospheric pressures, then vacuum pump II 2 corresponds different opening and stopping threshold values to ensure normal use of the automobile vacuum system, namely, for simulating plateau environment, each altitude corresponds to one atmospheric pressure, and vacuum pump II 2 corresponds to one opening and stopping threshold value under each altitude.
When a plateau environment is simulated, the altitude and the atmospheric pressure of the plateau environment to be simulated are input to the control module, and the control module automatically calculates the starting and stopping threshold values of the vacuum pump II 2 corresponding to the altitude and the atmospheric pressure; work of vacuum pump I1 reaches the atmospheric pressure value that required plateau environment corresponds to detecting the evacuation of simulation air chamber 3, work of vacuum pump II 2 is to car vacuum system evacuation, baroceptor I43 is used for detecting the atmospheric pressure in the simulation air chamber 3 and transmits for control module, baroceptor I43 is used for detecting car vacuum system's atmospheric pressure and transmits for control module, control module is according to opening and stopping of the relation control vacuum pump II 2 between the atmospheric pressure in the simulation air chamber 3 and vacuum system's atmospheric pressure, II 2 opening of vacuum pump stop frequency, the working time record is stored in control module, and show on display screen 5.
In order to enable the bench testing device to be suitable for different vehicle types, a controller 9 is arranged between the vacuum tank 41 and the booster 42, the controller 9 is communicated with a vacuum pipeline III 44 through a pipeline, and the controller 9 is electrically connected with the control module 6. The controller 9 comprises an integrated circuit board, a sensor for detecting the air pressure in the simulation air chamber 3 and a sensor for detecting the air pressure of the automobile vacuum system, the controller 9 can detect the air pressure in the simulation air chamber 3 and the air pressure of the automobile vacuum system, the integrated circuit board in the controller 9 can calculate the relation between the air pressure in the simulation air chamber 3 and the air pressure of the vacuum system and transmit the relation to the control module 6 so as to control the starting and stopping of the vacuum pump II 2.
The controller 9 integrates the air pressure sensor I43 and the air pressure sensor II 33, so that different air pressure detection modes can be selected according to actual vehicle types, namely the air pressure sensor I43 and the air pressure sensor II 33 are selected to detect air pressure or the controller 9 is selected to detect air pressure according to specific requirements. Similarly, the setting of the starting and stopping threshold value of the vacuum pump II 2 can set related parameters according to different requirements of customers, and the setting is carried out by adopting the following two modes: firstly, setting according to standard atmospheric pressure percentage, for example, setting the starting working threshold of a vacuum pump on a plain to be 50% P, and the stopping working threshold to be 25% P, and the like, and adopting a pressure sensor mode; secondly, setting starting and stopping thresholds according to different altitude intervals, for example, the altitude is below 2000m, the vacuum pump is started to a threshold value of-50 kpa, the vacuum pump stops working to a threshold value of-75 kpa, and the like, and adopting a vacuum controller mode.
Bench testing arrangement still includes brake pedal 7 and stopper 8, stopper 8 includes preceding stopper and back stopper, preceding stopper is the calliper form, the back stopper is calliper or wheel cylinder form, be equipped with brake master cylinder and booster push rod 421 on the booster 42, be equipped with the liquid storage pot on the brake master cylinder, brake pedal 7 passes through booster push rod 421 and is connected with booster 42, if distance overlength between brake pedal 7 and booster push rod 421, set up the extension bar between brake pedal 7 and booster push rod 421, brake pedal 7 is through extension bar and booster push rod 421, stopper 8 is connected through the master cylinder on hydraulic pressure pipeline 81 and the booster 42. The brake pedal 7 and the brake 8 are located outside the simulation air chamber 3. A force sensor is arranged on the force application surface of the brake pedal 7 and connected with the control module, so that the force of the brake pedal is monitored in real time, and the force value of the brake pedal is input to the control module; a stroke sensor is arranged on the booster push rod 421 and connected with the control module, so that the stroke of the booster push rod 421 is monitored in real time, and a stroke signal is input into the control module; a hydraulic pressure sensor is arranged on a hydraulic pipeline 81 connected with the brake 8 and is connected with the control module. The control module converts the stroke of the push rod of the booster into the stroke of a brake pedal according to the stroke signal of the push rod 421 of the booster, the pressure signal of the brake 8 and the lever ratio of the brake pedal, outputs the curve of the pressure of the brake 8 and the stroke of the brake pedal, and can read and store the curve on a display screen; the control module outputs a curve of the pressure of the brake 8 and the force of the brake pedal according to the force of the brake pedal and the pressure signal of the brake 8, and can read and store the record on the display screen 5. The control module is integrated with the display screen 5, the air pressure sensor I43, the air pressure sensor II 33, the vacuum pump, the brake pedal force sensor, the brake pedal travel sensor and the hydraulic pressure sensor are all connected with the control module, and the control module converts signals and displays the signals on a display screen interface. The bench test device for simulating plateau braking of the automobile is not limited by regions, can test and test the automobile vacuum system and the relation among the brake pedal travel, the brake pedal force, the hydraulic pressure and the vacuum degree of the brake pedal at different altitudes in the same place, realizes quick, simple and effective verification, reduces the development period and the cost of the automobile type, and creates value for enterprises.
In a high-altitude area, whether a vacuum system control strategy can meet the requirements of a whole vehicle or not, whether brake pedal force and travel under different altitudes meet vehicle requirements or not, a newly developed vehicle type cannot be confirmed in the early stage and can only be evaluated by means of experience and theoretical calculation, after the newly developed vehicle type is trial-manufactured and loaded, the whole vehicle is sent to a plateau area for testing, if parts in the brake system are unqualified, the parts need to be returned for re-manufacturing, the newly loaded vehicle is sent to the plateau area for testing again, so that the development period of the vehicle type can be prolonged, the development progress of the new vehicle type is restricted, and the marketing of the new vehicle type is influenced finally. The invention designs and develops a bench test device for simulating the plateau brake of an automobile, which can edit and input a vacuum degree control strategy into a control module 6, set the altitude and the atmospheric pressure of a simulation air chamber after the control strategy is input, step on a brake pedal, test and record the vacuum degree of an automobile vacuum system, the starting and stopping threshold values of a vacuum pump II 2, the working time of the vacuum pump II 2, the force of the brake pedal, the stroke of the brake pedal, the hydraulic pressure and other test values according to different forces, frequencies and the like applied to the brake pedal in the process, then compare the test values with theoretical values, further optimize the design of each part of the automobile brake system, finally install the optimized parts on the whole automobile, send the whole automobile to a plateau area for testing, thus equivalently, optimally designing the parts of the automobile before the test is sent to the plateau, the development cycle of new vehicle models can be shortened to a certain extent. If the parts need to be optimized for multiple times, multiple tests can be carried out on the plateau braking bench testing device of the simulated automobile, and the parts are sent to the plateau for testing when the braking system meets the requirements.
The invention also provides a use method of the test device for simulating the plateau braking bench of the automobile, which comprises the following steps:
step 1, inputting a vacuum degree control strategy of an automobile vacuum system into a control module, wherein the control module is integrated with a display screen 5;
step 2, when a plateau environment is simulated, the altitude and the atmospheric pressure of the plateau environment to be simulated are input into the control module, the vacuum pump I1 works to vacuumize the detection simulation air chamber 3 to reach the air pressure value corresponding to the required plateau environment, and the vacuum pump II 2 works to vacuumize the automobile vacuum system;
step 3, the control module 6 controls the starting and stopping of the vacuum pump II 2 according to the relation between the air pressure in the simulation air chamber 3 and the air pressure of the vacuum system, and the starting and stopping frequency and working time records of the vacuum pump II 2 are stored in the control module and displayed on the display screen 5;
and step 4, stepping on the brake pedal, testing and recording the testing values of the vacuum degree of the automobile vacuum system, the starting and stopping threshold value of the vacuum pump II 2, the working time of the vacuum pump II 2, the force of the brake pedal, the stroke of the brake pedal, the hydraulic pressure and the like in the process according to different force, frequency and the like applied to the brake pedal, and then comparing the testing values with theoretical values to further optimize the design of each part of the automobile brake system.
The working principle and the function of the air pressure sensor are as follows: the principle of the air pressure sensor is that the pressure resistance effect is utilized, the resistance value of a sensing element is changed due to air pressure, the internal resistance value forms a Wheatstone bridge, an external power supply supplies power, and when the pressure is different, the voltage is divided differently, so that the output voltage is converted into an air pressure value. Outputting a formula: vout VCC 0.00895P-0.09895, the output characteristic graph is shown in fig. 2.
The invention is described above with reference to the accompanying drawings, it is obvious that the specific implementation of the invention is not limited by the above-mentioned manner, and it is within the scope of the invention to adopt various insubstantial modifications of the technical solution of the invention or to apply the concept and technical solution of the invention directly to other occasions without modification.